Hypertensive retinopathy occurs when the retinal vessels get damaged due to elevated blood pressure.
The major risk for arteriosclerotic hypertensive retinopathy is the duration of elevated blood pressure. Other risk factors are:
- Afro-Caribbean race
- Female gender
Signs & Symptoms
Symptoms of hypertensive retinopathy include blurred vision or visual field defects.
Signs on fundoscopic examination
- Retinal hemorrhages: when necrotic vessels bleed into either the nerve fiber layer (flame-shaped hemorrhage) or the inner retina (dot blot hemorrhage).
- Arteriolar narrowing
- Moderate vascular wall changes (copper wiring) to more severe vascular wall hyperplasia and thickening (silver wiring).
- Retinal ischemia presents as cotton wool spots.
- Arteriovenous nicking-phenomenon where the venule is compressed in its caliber at both sides of an arteriovenous crossing.
- Formation of hard exudate
- Optic disk edema
Classification of Hypertensive Retinopathy
The extent and severity of the retinopathy is generally represented on a scale of 1 to 4. The scale is called the Keith-Wagener-Barker Classification System. The four grades increase in severity:
- Grade 1: mild narrowing of the retinal artery.
- Grade 2: similar to grade 1, but there are more severe or tighter constrictions of the retinal artery and arteriovenous nicking.
- Grade 3- Grade 2 + cotton-wool spots + micro aneurysms + retinal hemorrhages.
- Grade 4: Grade 3 + with optic disc swelling
Diagnosis of hypertensive retinopathy is made by the clinical appearance on a dilated fundoscopic exam and coexisting hypertension. It is important to note that background retinopathy (non-proliferative) may also have many similar findings on the fundoscopy which include microaneurysms (dots), hemorrhage (flame-shaped or blots), and hard exudates (yellow patches) but the history of uncontrolled hypertension makes hypertensive retinopathy a better choice.
Treatment for Hypertensive Retinopathy
Effective treatment for Hypertensive retinopathy involves controlling and lowering high blood pressure with a combination of medications and lifestyle changes.